Strange disease on clown killifish

confused_aquarist

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Hi there I’m Sue new to the forum. (Long wall of text ensues!) I’m wondering what this disease might be that’s affecting one of my killifish.

Couple of months ago I started a new aquarium and got 5 clown killies (siblings from a same breed) from an online pet store. The day that I got these fish I noticed that they were all sort of acting strange, not moving very much and not eating. Some of them never ate, some had stringy white poop and all but 1 female died one by one within 2 weeks. I should note that a common symptom seemed to be a bump below their mouths but never really figured out what that was. Also notably a day later I found the surviving female trying to spit out some white stringy stuff but failing over and over again as it went right back to her mouth. I never saw her do it again (and still haven’t to this day) so after a week I thought it might be smart to mix this surviving killi with another 5 clown killies I got from different pet store (a total beginner here so don’t be too harsh on me for this decision). For a month or so, they were actually doing fine. The surviving female started moving around a bit more after I mixed all 6 killies, and it had 4 fry in the meantime. I suppose I should mention that one of these fry has a tumor-looking bump, lies sideways on bottom of tank, and does not grow very much and so is not likely to survive for long.

So one day (exactly a month ago) this female started acting weird again and became less active, was hiding in moss all the time and developed a bump on its mouth, just like its 4 other siblings that died earlier. It also developed 4 red/black spots on its forehead, and lips turned blood red though didn’t seem to be injury or fungus as it definitely didn’t appear to be an outgrowth (light colored Lillie in the 1st photo). 2 of these spots are near where its nose would be, and two other ones follow right behind them, and they’re symmetrical. Can’t tell if they’re holes or if internal since these holes are just way too tiny for poor me to see on this small fish.

A day later, a tank mate developed gill disease and two days later died from dropsy. The 4 remaining tank mates still appear normal to this day.

So in the meantime I quarantined this female and gave an antibiotic bath treatment, and while in this bath the female developed fin rot in addition to the mouth bump that it already had, but within 2 weeks both the fin rot and mouth bump went away. But then it started pooping out white strings and so I bought a microscope and found fast-moving flagellates coming out from its poop. The tiny flagellates and would stop moving in a few minutes after coming out of poop so I assumed it was something anaerobic.

So, fast-forwarding 2 weeks later, here is what this female looks like now (photo 2). It doesn’t eat at all anymore, has a bent tail (always bending to the left) and the 4 red/black spots on its forehead which never went away with antibiotics have turned even darker. Also I noted 2 tiny black dots on its belly, right at the bottom of its 2nd band (photo 3). I can’t tell since the fish is small, but the dots seem to be internal as the bottom part of its belly is translucent, or at least that’s my suspicion. This killie has been floating around for a few days and I’m honestly now considering euthanizing it since it’s probably going to be gone in a few days anyway.

I tried to do some treatments with metronidazole, but here in Japan unfortunately it took 2 weeks for me to obtain the drug from an overseas seller and by the time it arrived the fish pretty much wasn’t eating at all. Still tried to put some in the quarantine bath but not too sure if that was having any effect.

At the moment I’m suspecting hexamita, but not sure if that’s the whole story here. Here in Japan we have almost no fish drugs, just some anti-ich and antibiotics for treating columbaria and sorts, so honestly I wouldn’t be surprised regardless of what this is. To be completely precise, my prediction based on these symptoms would be hexamita with concurrent fish TB infection but would appreciate any input to help figure out what this could be. So many mysterious symptoms!
 

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I'm going to sound horribly unscientific. I have never seen that on a killie, but I have sometimes on Cichlids. It's affected Cichlids from Guinea only. E, annulatus also comes from that region, and is often wild caught.

I don't know if it is viral or bacterial. Fish hit with it look good for 2-3 months after arrival, and then I guess the stress of tank life gets to them. Once it appears, nothing saves the fish. Oddly, while I have seen this 4 or 5 times of my many years of keeping African riverine fish, it has never spread to other tankmates, or non northwest African fish.

It seems illogical, but I can only report what I have seen.

It's a little different with your fish, but it's also a different fish family.

In the debatable case I'm right, you can't do a thing. I'm guessing it works like Mycobacter and sits dormant for long periods, but it presents differently. It has always killed all the affected fish. It's the mysterious "Guinea plague".

Hopefully someone else can be more helpful. It's ugly, weird and destructive.
 
I'm going to sound horribly unscientific. I have never seen that on a killie, but I have sometimes on Cichlids. It's affected Cichlids from Guinea only. E, annulatus also comes from that region, and is often wild caught.

I don't know if it is viral or bacterial. Fish hit with it look good for 2-3 months after arrival, and then I guess the stress of tank life gets to them. Once it appears, nothing saves the fish. Oddly, while I have seen this 4 or 5 times of my many years of keeping African riverine fish, it has never spread to other tankmates, or non northwest African fish.

It seems illogical, but I can only report what I have seen.

It's a little different with your fish, but it's also a different fish family.

In the debatable case I'm right, you can't do a thing. I'm guessing it works like Mycobacter and sits dormant for long periods, but it presents differently. It has always killed all the affected fish. It's the mysterious "Guinea plague".

Hopefully someone else can be more helpful. It's ugly, weird and destructive.
Well this is still somewhat informative!

From what I’ve heard from the pet store employee, this isn’t a wild-caught individual, but I wouldn’t be surprised if it’s transmissible from mother to offspring through generations as I clearly suspect from one of the fry. Do you mind sharing, what specific symptom made you suspect that this is “Guinea plague?” I’ve never heard of it and just want to know more about it.
 
I almost didn't post, because it's such a vague observation, and I have never read a reference to it. Guinean fish aren't popular, or talked about much.

It always started with swelling around the throat and gills, affecting the mouth. It took on a bump shape, behind the mouth along to the gills, and the fish stopped eating and became discoloured. They would become listless, and the dead bodies would always have a wide open mouth.

The last time I saw it, I had a perfectly healthy looking pair of dwarf Cichlids - 2 fish in a well maintained 40 gallon, engaged in pre-spawning one day, then dead 3 days later. Nothing in their behaviour or appearance warned me, although I've learned to be wary with fish from that region.

I'm mainly a killie keeper, and I haven't seen anything like this with them.

Your description of the bump around the mouth made me look twice. I think as aquarists, we always want to reduce the complexity of what we see, because we aren't equipped to understand it. There are diseases that aren't in our books, just from the complexity of living organisms. We want to name things, but sometimes they are unnamed, or we don't have access to the papers that name them.

Imagine if human medicine were reduced to some antiparasitics and randomly chosen over the counter antibiotics?
 
I almost didn't post, because it's such a vague observation, and I have never read a reference to it. Guinean fish aren't popular, or talked about much.

It always started with swelling around the throat and gills, affecting the mouth. It took on a bump shape, behind the mouth along to the gills, and the fish stopped eating and became discoloured. They would become listless, and the dead bodies would always have a wide open mouth.

The last time I saw it, I had a perfectly healthy looking pair of dwarf Cichlids - 2 fish in a well maintained 40 gallon, engaged in pre-spawning one day, then dead 3 days later. Nothing in their behaviour or appearance warned me, although I've learned to be wary with fish from that region.

I'm mainly a killie keeper, and I haven't seen anything like this with them.

Your description of the bump around the mouth made me look twice. I think as aquarists, we always want to reduce the complexity of what we see, because we aren't equipped to understand it. There are diseases that aren't in our books, just from the complexity of living organisms. We want to name things, but sometimes they are unnamed, or we don't have access to the papers that name them.

Imagine if human medicine were reduced to some antiparasitics and randomly chosen over the counter antibiotics?
It's definitely good to know that there are diseases beyond the most common ones in the hobby. It just doesn't seem to fit in with any of the descriptions where I searched online. When I got the killies I just thought wow that bump on the mouth is strange. At first I suspected it had to do with inbreeding issues.
I think what I'm going to try to do is in a few days cut it up and examine on the microscope just to make sure there aren't any tubercles or things of that sort because I feel like that could change things up a lot.
This has to be one of the few times where I regret leaving my former science job for doing house chores since where I live it's incredibly difficult to send things in for pathology. Curious as hell what this could be.
 
I have no background in laboratories. I'd be delighted if you could share what you find. My guess could be based on total coincidence.
 
Fish that stop eating normally and pick at little bits of food but not a lot, and do a stringy white poop, then die a couple of weeks later usually have an internal protozoan infection. Metronidazole is the medication of choice. You add it to the tank and let the fish absorb it into their body. If you treat the fish early there is a good chance of survival. However, if left too long the protozoa do major damage to the internal organ/s and the fish dies.

The following link has info on stringy white poop in fish.

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The red area in the fish's face/ head is an infection in the brain, face or throat area. It is usually bacterial but can also be from a virus, protozoa or fungus. It stops fish eating and they usually die within a week or two of showing the red area. It is commonly seen in dirty tanks or tanks with a lot of rotting gunk in, that includes the filter as well as the substrate. If the fish had it within a week of being in your tank, they probably had it at the breeders or shop and were kept in less than clean conditions. Cleaning the tank up (including filter and gravel) and adding salt (2 heaped tablespoons per 20 litres for 2 weeks) or a broad spectrum medication can usually stop it spreading to other fish but the fish that show symptoms usually die anyway.

I can't tell much else from the pictures.
 
Fish that stop eating normally and pick at little bits of food but not a lot, and do a stringy white poop, then die a couple of weeks later usually have an internal protozoan infection. Metronidazole is the medication of choice. You add it to the tank and let the fish absorb it into their body. If you treat the fish early there is a good chance of survival. However, if left too long the protozoa do major damage to the internal organ/s and the fish dies.

The following link has info on stringy white poop in fish.

-------------------

The red area in the fish's face/ head is an infection in the brain, face or throat area. It is usually bacterial but can also be from a virus, protozoa or fungus. It stops fish eating and they usually die within a week or two of showing the red area. It is commonly seen in dirty tanks or tanks with a lot of rotting gunk in, that includes the filter as well as the substrate. If the fish had it within a week of being in your tank, they probably had it at the breeders or shop and were kept in less than clean conditions. Cleaning the tank up (including filter and gravel) and adding salt (2 heaped tablespoons per 20 litres for 2 weeks) or a broad spectrum medication can usually stop it spreading to other fish but the fish that show symptoms usually die anyway.

I can't tell much else from the pictures.
That makes a lot of sense. I think the metronidazole treatment happened way too late and the fish could be dying from the internal organ damage.

Now that I think about it maybe it did have some sort of infection around the head area, probaby due to weakened immune system. I guess a ton of different things could be happening. Maybe the bump was also just an infectious nodule to spread contagious pathogen.

Do you think that the symptoms could still be consistent with fish TB? That's my primary concern because I'm most worried whether it could've spread to the fry and other fish.
 
I doubt it's TB due to the fact killifish are normally kept in cooler water (low 20s Celsius) and only live 1-2 years. They wouldn't live long enough to die from TB even if they do contract it. Most killifish are also kept in single species tanks and don't come from Asian fish farms where Mycobacteria is common.

In my experience, fish with Mycobacteria infections usually act normally until one of their internal organs is severely damaged by the Mycobacteria. Then the fish bloats up overnight, stops eating, does a stringy white poop, breathes heavily at the surface or near a filter outlet, and dies within 24-48 hours (usually 24) of showing these symptoms. They don't do stringy white poop and go off their food for 2 weeks before dying (that's an internal protozoan infection). When Mycobacteria damage an internal organ, the fish dies rapidly from organ failure.
 
I've kept and bred killies for 35 years, and haven't seen anything that resembled tb in that time. I've stopped keeping rainbows because of tb, and have seen it on livebearers as well. I'm unfortunately no stranger to Myco in tanks. But my killies, including many years of annulatus, have never shown signs of it.
 
I doubt it's TB due to the fact killifish are normally kept in cooler water (low 20s Celsius) and only live 1-2 years. They wouldn't live long enough to die from TB even if they do contract it. Most killifish are also kept in single species tanks and don't come from Asian fish farms where Mycobacteria is common.

In my experience, fish with Mycobacteria infections usually act normally until one of their internal organs is severely damaged by the Mycobacteria. Then the fish bloats up overnight, stops eating, does a stringy white poop, breathes heavily at the surface or near a filter outlet, and dies within 24-48 hours (usually 24) of showing these symptoms. They don't do stringy white poop and go off their food for 2 weeks before dying (that's an internal protozoan infection). When Mycobacteria damage an internal organ, the fish dies rapidly from organ failure.

I've kept and bred killies for 35 years, and haven't seen anything that resembled tb in that time. I've stopped keeping rainbows because of tb, and have seen it on livebearers as well. I'm unfortunately no stranger to Myco in tanks. But my killies, including many years of annulatus, have never shown signs of it.

Okay. I think that there's little doubt that this particular individual was dying from protozoan infection but again my gut feeling tells me that something else might also be going on. Actually this morning, I found that one of the males (from the different pet store) was developing a bump below its lips, at the exact same spot. It has been showing signs of it since 2 days ago with the tip of the lip turning white, but I did not think this would turn into a bump. I'm going to watch out for protozoan for now, since I feel it may just be the way that these killifish are expressing protozoan symptoms. Though again I could be totally wrong. At least I have some drugs ready this time so I could start the treatment whenever. This is frustrating! I'm worried about the remaining fish, worried about the fry, :(
 
I doubt it's TB due to the fact killifish are normally kept in cooler water (low 20s Celsius) and only live 1-2 years. They wouldn't live long enough to die from TB even if they do contract it. Most killifish are also kept in single species tanks and don't come from Asian fish farms where Mycobacteria is common.

In my experience, fish with Mycobacteria infections usually act normally until one of their internal organs is severely damaged by the Mycobacteria. Then the fish bloats up overnight, stops eating, does a stringy white poop, breathes heavily at the surface or near a filter outlet, and dies within 24-48 hours (usually 24) of showing these symptoms. They don't do stringy white poop and go off their food for 2 weeks before dying (that's an internal protozoan infection). When Mycobacteria damage an internal organ, the fish dies rapidly from organ failure.
And sorry for double-posting but in case of protozoan infection (since a different tank mate has started to show a symptom), do you think that it would be worth treating the whole tank with metronidazole. The tank has live plants and floating plants. I'm also worried that it would disrupt the bacterial cycle, since it could result in mass bacteria death and rotting plant is not degraded, causing worsening of water quality that would stress fish.
 
Metronidazole only treats internal protozoan infections. Unless the fish are doing stringy white poop and not eating much, there is no need to use Metronidazole.

External protozoan infections appear as small white dots like grains of salt on the body and fins (Ich or white spot disease); a yellow or gold sheen over part of the body (velvet); or cream, white or grey patches on part of the body (Costia, Chilodonella, Trichodina). All these external protozoan infections cause the fish to rub on objects and show visual symptoms. You can treat external protozoan infections with Malachite Green or copper. Salt can be used to treat Costia, Chilodonella & Trichodina. However, salt won't treat white spot or velvet but heat (30C for 2 weeks) can be used or copper or Malachite Green.
Salt, copper and Malachite Green will not treat internal protozoan infections.

The white bump on the fish is unlikely to be protozoan. I need clear pictures showing the white bump on the fish.
 
Metronidazole only treats internal protozoan infections. Unless the fish are doing stringy white poop and not eating much, there is no need to use Metronidazole.

External protozoan infections appear as small white dots like grains of salt on the body and fins (Ich or white spot disease); a yellow or gold sheen over part of the body (velvet); or cream, white or grey patches on part of the body (Costia, Chilodonella, Trichodina). All these external protozoan infections cause the fish to rub on objects and show visual symptoms. You can treat external protozoan infections with Malachite Green or copper. Salt can be used to treat Costia, Chilodonella & Trichodina. However, salt won't treat white spot or velvet but heat (30C for 2 weeks) can be used or copper or Malachite Green.
Salt, copper and Malachite Green will not treat internal protozoan infections.

The white bump on the fish is unlikely to be protozoan. I need clear pictures showing the white bump on the fish.

Here are some photos of it. There is a pinkish lump right at the tip of bottom lip.
Actually, I have seen this in clown killies of other fish keepers. I ask them about it, and they say they too have lost several fish it so I think it seems to be an issue with some recent breeds.
 

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It looks like a fat lip from swimming into something. Newly caught rainbowfish get it too from swimming into the glass or jumping and hitting the coverglass.

It could also be the start of Columnaris (mouth fungus) but it doesn't look like that to me. Columnaris is a fast growing bacterial infection that starts off as a white lip and spreads over the face and head within 24-48 hours. The fish usually dies at this stage. If the fish has had the same patch for a few days and it hasn't spread, it's unlikely to be Columnaris.

We use salt with rainbowfish that have a fat lip and it seems to help. You can try it for a week and see if it helps. If not we will need to investigate further. But it's not a normal disease as such and looks more like mucous covering a damaged area (fat lip).

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SALT
You can add rock salt (often sold as aquarium salt), swimming pool salt, or any non iodised salt (sodium chloride) to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres (5 gallons) of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for 1 to 2 weeks.

The salt will not affect the beneficial filter bacteria, fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

When you first add salt, add the salt to a small bucket of tank water (2 litres or 1/2 gallon) and dissolve the salt. Then slowly pour the salt water into the tank near the filter outlet. Add the salt water over a couple of minutes.
 

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